The Keurig model in question is the Mini, the one where you add water before each brew ... not the larger model that has a water reservoir on the side. The affected models have a model number of K10 and in identification number starting with 31 printed on the bottom of the unit.
If you own one of these units, a kit is available from Keurig that will correct the problem. You can click here for more information or to fill out a from to request your kit.
I bought one of these coffeemakers a couple of years ago, but I'm not a fan. I don't particularly care for the flavor of the coffee brewed in a Keurig. I've tried a lot of different flavors of K-Cups, and I've tried using the reusable K-Cup with my own coffee. I still didn't care for the taste. Also, when I drink coffee in the mornings, I like to add more coffee as I drink it to keep it warm ... and you can't do that with a Keurig. It seemed like such a good idea, and there are some people who love their Keurig ... but I'll stick with my good 'ole Mr. Coffee.